This is meant to be a safer alternative since
NULL can often be 0. Let's not rely on that.
And yes, I know this is a lot of files. This is
a safer thing to do in big commits vs for loops.
0: 'Keyboard' axes: 0, hats: 0, buttons: 256 (buffered)
1: 'Mouse' axes: 3, hats: 0, buttons: 8 (buffered)
So let's get this straight:
Left, Right, and Middle clicks work.
Wheel Up and Wheel Down work.
X/Y axis doesn't seem to work yet.